<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .time-line{
            width: 700px;
            background-color: khaki;
            min-height: 700px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
        }
        .time-line .item{
            width: 300px;
            min-height: 100px;
        }
        .time-line .item:nth-child(odd){
            background-color: pink;
        }
        .time-line .item:nth-child(even){
            background-color: green;
        }

    </style>
</head>
<body>
    <div class="time-line">
        <div class="item">1</div>
        <div class="item">2</div>
        <div class="item">3</div>
        <div class="item">4</div>
        <div class="item">5</div>

    </div>
</body>
</html>